1. Field of the Invention
The present invention relates to a computer system capable of operating both first-language application software and second-language application software utilizing one computer, one input/output device and one first-language OS, and more particularly to a computer system having an emulator for executing Japanese application software on a computer running under an English OS while maintaining a software interface for English application software and its emulator.
2. Description of the Related Art
Heretofore, a personal computer handling the Japanese language has had a unique architecture different from that of a personal computer handling English language and an operating system (hereinafter abbreviated OS) is also supplied in a Japanese-processing-facility added form.
However, personal computers for business use led by the United States of America extensively use the IBM-supplied PC/AT architecture. Several tens of thousands of pieces of excellent application software developed for the PC/AT architecture have been sold. For this reason, in the personal computer world, the PC/AT architecture has generally been recognized as the world standard, and thus personal computers of the same architecture have been manufactured and sold by many companies.
On the other hand, in order to realize the Japanese environment on the PC/AT architecture, the addition of hardware, such as a modified keyboard and a Kanji font ROM, have been required. Following this, modifications of the basic input/output system (BIOS) which is a basic input/output control program and the OS are required.
FIG. 1 is a block diagram of a system for utilizing English application software (hereinafter referred to as English application) with the English 10 MS-DOS prepared by Microsoft Corporation in U.S.A. Also, FIG. 2 is a block diagram of a system for utilizing Japanese application software (hereinafter referred to as Japanese application) with the Japanese MS-DOS. As is evident from the comparison of FIG. 1 with FIG. 2, in the case of personal computers handling Japanese applications, the Japanese MS-DOS (hereinafter referred to as the Japanese DOS) is provided in place of the English MS-DOS (hereinafter referred to as the English DOS) and the Japanese BIOS is newly provided.
To operate a Japanese application and English application on one personal computer, there is a method which uses two types of OSs, the Japanese DOS and English DOS.
According to this method, the OSs have only to be equipped with their respective facilities. From the standpoint of users, however, a drawback with the method is that operation is troublesome. That is, by way of example, in order to execute an English application after execution of a Japanese application, the English DOS has to be activated before the execution of the English application. There is also a drawback that two types of OSs have to be installed on a disk.
There is another method which incorporates an English-compatible facility into the Japanese OS. This method has an advantage that one OS permits Japanese and English applications to be operated, but on the other 10 hand the method has a drawback that a free area left for the English application is reduced in memory because a section for the Japanese facility is resident permanently in the memory. Moreover, since the DOS is not the English DOS proper, there is a drawback that there is not any guarantee that compatibility with the English DOS environment can be maintained. Furthermore, there is a drawback that the whole OS has to be looked over again for revision with each succeeding version of the OS.
In either of the two methods, no consideration is given to printers. That is, printers adapted for a Japanese must be used for Japanese application, while printers adapted for an English must be used for English application. This is very inconvenient.